Coffee roasting machine



Feb. 1,1944. I s.s.fmm:s l 2,340,345

1 i I COFFEE IQZOASTING MACHINE,"

Filed play 25, 194.1 5 Sheets-Sheet 1 HO m SA FO D ER/cI /EsQN INVENTOR.

ATTORNEY Feb. 1, 1944.

s. E. RICHESON COFFEE ROASTING MACHINE Filed May 25, 1941 5 Sheets-Sheet 2 SA NFORD ER/cHEso/v INVENT OR.

9% k-mw ATTORNEY Feb. 1, 1944. H s, RI CHES O N 1 2,340,345

COFFEE ROASTING MACHINE Filed {day 23, 1941 5 Sheets-Sheet 5 FIGS SA NFORD E R/cHesoM INVENTOR.

R you n ATTORNEY the roasting container, directed onto theeoflee two different directions,

the exhaustgases from t Patented Febi l,

COFFEE BOASTING moms J Smith E. Bioheson, Brooklyn, N. Y. Application May 2:, 1941, was. 394,788

3 claims (or 84-56) My invention relates to coffee roasting macally operated automatic roasting machines.

My invention hasv for its object to provide an entirely automatic roasting machine in which green or raw coflee is automatically delivered into i chines and has particular reference to electri- I a roasting container when temperature in the chamber rises to a predetermined limit, the roasting process being continued until, all the coflee beans in the container are heated to a roasting temperature; when the roasted product is automatically dumped into a coolingreceptacle where coifee is separated from the chaff. By properly fadiusting suitable temperature responsive devices, a. perfect roast can be obtained.

Another object of my invention is to provide means for roasting coflee exclusively by radiated heat from a source placed entirely outside "the radiant heat being beans preferably from effect of cross-radiant heat. The heat rays pass thereby obtaining the until the coffeein the roasting container is fully roasted and discharged.

My invention is more fully described in the accompanying specification and drawings,- in whichz.

Fig. 1 is a sectional elevatlonai view of my machine; j I i "Fig. '2 is an elevational view from the driving sidewith one wall of the casing removed;

through the walls of the container made or a A material transparent to infra red rays. 'I have found that a more satisfactory roasting can be obtained by this method, the

cross-radiant heat penetratingdeeply into the coflee beans. while with the other roasting methods involving heat conduction and convection, the roasting is largely confined to the surface of the beans. Moreover, the radiant heat produces more uniform product and of a better quality compared to the roasting by convectiomin the latter case a large of volatile aromatic substances being drivenout. of the coffee by the strong air current.

Another object of myinvention is to provide an eiiiclent smoke absorbing device i'or purifying the machine, so that the machine can bemused in an ordinary store or similar confined place. best results are obtained gases are blown throughwater and glass wool. or similar inerttlbrous absorbing material. I

I have'i'ound'that smoke elimination is made i more eflective if pressure impulses are applied to the smoke under ahead of a. water column, thus causing fine dust particles to coalesce into large lumps, rendering the-glass wool absorbing.

Still another object of my invention is to provide an arrangement whereby the machine cannot be stopped with green or partly roasted coffee in the roasting chamber. This-is accomplishedlnmy machine by the use of a switch control device, which, when set. for disconnecting I have found that the. when thesmoky exhaust i Fig. 3 isv a fractional elevational view from an other side;

Fig. 4 is a diagram of electrical connections; Fig. 5 is atop plan view with the cover re- Fig. 6 is a developed view of the cams controlling operations of the machine; v

Fig. 'lisa detail viewof a thermostatic switch. Fig. 8 is an enlarged detail view of the roasting cylinder. i l 1 My coifee roasting machine consists of a frame I preferably made ofmetal bars and having a top plate 2 below a cover plate 3. The latter rests on an outer casing or housing 4,.preierably made or sheet metal or Bakelite" and having an attractive finish, being enameled or otherwise decoamount iorthe end portion of the. cylinder.

A roastingcylinder under the plate 2. It is preferably made or a heat resistant transparent material, such as glass "Pyrex" or similar glass having high silica con v tent.

The front end of the cylinderrests against the flange of a cone-shaped end bell 8, preferably made of sheet metal and inturn resting. against the flangeof an end member I. A clearance 8' is formedbetween the'end bell ber, air inthe clearance forming'heat insulation The end a tubular a bearing 9 on a bracket Ill bar it. The outer end of member 1 is integrally connected with shaft 8 :iournaled in mounted on a cross the shaft mounts an eccentric cam i2 and a w the switch, retains the. switch closed. however.

.pulley it connected by driving pulley 2! on the a V-belt H or similar flexible driving member with a pulley I! on an intermediate shaft, i8 lournaled ina bearing ll.

mounted on a cross bar It. A large pulley i9 is also mounted onthe shaft ll and is connected by a belt 2| or similar flexible member with asmall electric motor 23. The enclosed type with an blowing air through an take P pe 1 2'.

motor is preferably of an exhaust pipe 24 and inpulleys it is possible to drive the at a relatively slow speed. 1

5 is placed horizontally and'the end mem end of the shaft of an i internal cooling fan :r- 1

With such an arrangement of roasting cylinder hopper.

A metal ring is placed-against the rear. end of the cylinder 5, supporting bent-over ends of metal bars 21, extending in an approximately radial direction and serving as stirrers for the coffee beans in the cylinder. The front ends of the bars 21 are bent inward, being attached to the cone 6. The bars 21, besides stirring the coffee, complete a skeletal structure supporting the glass cylinder 5. A ring 28 is attached to the ring 26 over the ends of the stirring bars 21 and is provided with arms or spokes 29 extending to an inner ring 30. The latter supports the flange of an inverted cone 3I preferably made of a heat resistant glass such as Pyrex which is transparent to infra red rays from a heating electric lamp 32.

The lamp is fitted in a socket 33 supported on the frame I inside of a short tubular member 34. The tubular member forms a bearing for a conical tube 35 enclosing the lamp. The tube acts as a reflector for the heat rays of the lamp, directing them against the glass cone 3|. The large rear end of the tube 35 is tapered outward at 36 and has a flange 31 closely approaching the ring 28. A second conical flange 39 extends ,from the tube 35 toward the rear end of the cone 3|. Small clearances are provided between stationary parts and the rear end of the cylinder so as to prevent the escape of the coffee beans from the cylinder. The amount of air admitted into the cylinder may be regulated by a shutter 30' sliding over holes 3I in the'flange 36.

The tapered portion 36 has an opening 40 at one place registering with a bottom opening of a hopper 4| when the tube 35 is turned in a corresponding position. The hopper 4I extends from an opening 42 in the plate 2 under a rotary feeder 43. The feeder represents a tubular cylinder with a top plate 44 placed substantially below the upper edge of the cylinder and is mounted for rotation on a short shaft 45. The feeder has an arcuate transverse opening 46 between walls 4'I, passing under the lower end of an upper hopper 48 extending from a glass tube 49 on top of the machine with a cover 50, the tube 49 and the hopper 48 containing green or raw coffee beans. The lower end of the hopper 481s raised above the plate 44 in order to prevent crushing of the beans by the edges of the vent the escape of coffee from the feeder to the outside. The feeder is rotated by a pawl 50 engaging teeth 5I on the lower flange of the feeder.

The pawl is pivoted at 5I' in the forked end of a shaft 52 journaled in a bearing 53 supported on a bracket 54.

An arm 55 is keyed to the outer end of the shaft 52 and has a fork 56 with rollers 51 engaging the sides of the cam I2. The cam causes the forked arm 56 to oscillate, thereby oscillating the pawl 50. The latter engages the teeth 5I when an armature 58 on the upper end of the pawl is attracted by a magnet or solenoid 519.. A dog 52 with a spring 53' prevents back slipping of the feeder. A counterweight I45 keeps the armature away from the magnet 59.

The peripheral surface of the feeder cylinder is provided with cams 60, BI, 62 and 63 shown more clearly in Fig. 6, which represents developed view of the peripheral surface of the feeder and developed view of the opening 45. Cams and62 act on a roller 54 on the end of an arm 65 connected by a shaft 66 with an arm 6?. the shaft 66 being journaled in a bearing 88 mounted on the plate 2. The free end of the arm 57 The raised edges of the feeder 43 preis pivotally connected at 69 to the upper end of a link I0 whose lower end is pivoted at H to lug 12 on the rotary cylinder 35. The arms and the ,link are so proportioned that the earns 60 and 62 alternately turn the tube 35 so as to bring the opening 40 to the bottom or to the top of the cylinder 5, thereby discharging the roasted coffee or charging raw coffee into the cylinder 5.

The cams BI and 63 are engaged by a lug I3 on an arm I4 connected with a shaft I5 supporting a mercury switch 16 and journaled in bearings TI on the plate 2. The switch is normally closed by a weight I6, closing the circuit for the solenoid 59 (see also the diagram in Fig. 4) by leads 18, 19 and 80. The cams BI and 83 open the switch. The solenoid is also connected with the bus bar line 8| by a thermostatic switch 82 which closes the circuit through leads I9, and 80' when a certain predetermined temperature is reached in the roastingcylinder 5. The thermostatic switch is mounted on a rod" 83 extendingthrough the hollow shaft 8 and supported at the end in a bracket 84 extending from the frame I.

The main circuit may be disconnected by a mercury switch 85 mounted on an arm 86 pivoted at 81 between brackets 88 resting on the plate 2. The inner end of the arm 86 is longer and heavier than the outer end, so that it tends to turn the switch into a disconnecting position. The switch stays closed, however, the arm 85 being supported by a pin 89 at its end, the pin sliding over the inner surface of the feeder flange. The flange is provided with a hole into which the pin 89 falls, allowing the arm 86 to turn and the switch 85 to be disconnected. If it is desired to continue operation of the machine. then the outer end of the arm 86 is depressedby turning a knob 9I on a vertical shaft 92, thus causing a lug 93 on the shaft to climb on a tapering end 94 of the arm 86 and depressing the latter. For stopping the machine, the knob 9I is turned to the left, removing the lug from the arm 86. The switch 85 will then be turnedinto an open position when the pin 99 meets the hole in the flange 90. The hole is so placed that the machine stops at the end of the coffee discharging operation and before the feeder is opened for charging fresh coffee into the cylinder 5.

The smoke which collects inside the casing is exhausted by a positive reciprocating pump. It consists of a bellows 95 made of an elastic material such as rubber and operated by an arm 96 attached to the end of a shaft 91 journaled in bearings 98 mounted on the plate 2. The other end of the shaft 91 is fastened to the end of a bar 99 pivotally connected to the end of a crank bar I00 pivotally mounted on a crank IOI extending from the pulley I9. The crank bar reciprocates during rotation of the pulley I9, oscillating the shaft 91 and operating the bellows 95. The bellows is mounted on the plate 2 which has two holes, an intake hole I02 with an intake valve I03, and an exhaust hole I04 with a valve I05. The valves are preferably made of rubber so that they will seal the ports even if small dust particles may be lodged under them. The casing or housing 4 is air-tight and collects smoke emerging from the cylinder through clearances between parts 28, 31 and openings between the spokes 29, the smoke being then drawn through the hole I02.

. In view of the fact that the smoke may contain a certain amount of tars which may cause sticking of the valves. means is provided for -the suction movement of the bellows.

their positive operation. The intake valve I03 (is provided for this purpose with wire loops I06 off its seat at the end of The intake valve is positively opened at the end of the exhaust movement of the bellows by a wire or rod I01.

which pull the valve or serrations III. I have found that glass wool very effectively absorbs smoke particles, particularly in view of the fact that the smoke, being subjected to high pressure, surges in the exhaust pipe caused by the bell, escaping all The smoke is forced through a flexible tube I08 into a smoke collector or eliminator consisting the cylinder is dis the reciprocating action of the pump bellows, and under static head of water column, have tendency to coalesce into into water, where they I6 or with pulley on belt I IZI. .Cooling air is admitted into a chamber I22 under the pan by a fan, the. hot air being I24 to the outside.

A small opening I25 is provided' in ral wall pipe I23 from the motor exhausted through a pipe partment I26. The roasted coffee is removed from this compartment through a door I21.

A lamp I28 in a reflector I28 is. provided at the side of the cylinder 5 for producing cross.- radiant heat and also for illuminating its contents. The cylinder can be observed through a tube I20 inserted into the wall 4 (Fig. 2) and extending to the cylinder 5 wherea condenser or magnifying lens I29 may be provided. I The outer end of the tube I 29 is covered witha convex glass plate I30. A second glass plate I3I is placed at a distance from the first plate I30 the housing by an asbestos gasket I36. A brass riveted to the cover at I38 and engages a contact lever I 39 pivoted at I42 witha contact point I engaging a contact point I4I when the temperature in the housing reaches a ,sponding hole in the flange current will energize the motor 23and the heatwill not rotate since cylinder 5 weight 16';

mitting heat by'conduction to the brass bar I37,

so that the switch is closed only when the beans reach the desired roasting temperature.

The operation of my machine is as follows: Green coffee is placed in the hopper 48 and glass container 49. The coffee spreads over the top of the feeder and fills the cavity or recess 46. The coffee cannot reach the roasting cylinder 5, however, since the recess 46 does not register with the opening 42. The opening 40 is now at the top, being placed there by the cam 62 upon completion of the preceding discharg-.

ing operation. Cam 63 at the beginning of the operation keeps the solenoid circuit disconnected until it is closed by the thermostat.

The main switch 85 is closed by turning the knob 9|, therebydepressing, the outer end of the arm 86 and. removing pin 89 from the corre-.

of the feeder.

the jSOlEIlOld." The latter will attract the armature 58, bringing thepawl 50 with theteeth 5| of the feeder flange.

in engagement with the teeth 5I.

As shown in Figs. 5 and 6, soon after the feederstarts its rotation, the recess over the opening 42 in the plate 2. The coffee will then flow into the hopper H and into the through the opening M. The thermostat .will be cooled off by the fresh coffee but the circuit for the solenoid will be kept closed by the mercury switch I6, turned down by the The feeder will continue. rotation,

. dischargingthe coffee into the roasting cylinder until the opening or. recess 46 moves out of register with the opening 42. Rotation will continue until the cam 6I reaches the switch 16 and opens the same, thereby deenergizing the solenoid and stopping rotation the thermostatic switch .being also opened by the cooling effect of the raw coffee.

The feeder will now stand still while temperature of the coffee gradually reaches the roasting point. As soon as the right temperature is reached, the thermostat will close the circuit feeder.

for the solenoid, starting againrotation of the Cam 60 will turn the opening 40 downward for discharging the roasted coffee, this operation continuing until the cam 62- turns the opening upward again. Rotation will continue if the thermostat is still at the right temperature or will stop until this temperature is reached. It will stop in any event, however, if the knob SI is turned to the leftreleasing the bar. 86 and allowing the pin 89 to engage the hole in the feeder flange.

. The roasted coffee can be removed from the compartment I26 by opening the door I2'I.

pan I2I with the accumulatedchaif can be also, I

removed for cleaning. The containers I09 and H2. can be cleaned and refilled from timeto time. These containers may be kept at a distance from themachine, in the cellar if so desired. I

With my machine and roasting method it is possible to obtain a very fine roast due princi- The 46 will pass pally to the very low loss of moisture content in I the beans. The use of radiant heat exclusively.

eliminates the necessity of blowing air through the roasting chamber, so that there is no excessive drying of the beans, there being only coffee in the hopper 48 is roasted.

In order to stop the operation of the machine when the supply of raw coffee is exhausted, an

. automatic stopping device is provided for turning off the shaft 92. The device consists of a vane I41 pivotally supported at I48 in the lower portion of the hopper 48 (the vane may be preferably made to extend to the bottom of the hopper). The vane has an arm I49 extending to the outside of the hopper through a suitable slot in its wall. A weight I50 is placed on the arm I49 to keep it down so as to raise the vane I41. I

The arm is pivoted at II to a rod I52 engaging a hook I53 pivoted at I54 to a lever I55. The

lever is pivoted at I56 to the plate 2, its other end engaging a lug I51 onthe rod 92.

the roasted coffee from the cylinder upon completion of the roasting process.

2. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mount- 5 ed at one end in the framework, a closure partly The weight of the raw coffee in the hopper normally keeps the vane I41 down and the rod I52 with the hook I53 raised, leaving the lever I55 inoperative. If, however, the supply of the raw coffee is exhausted, the vane I41 is allowed the lever I55 until its outer end engages the lug I51, turning the rod 92 and moving the lug 93 away from the arm 94. The arm 94 is then released so that the pin 89 can enter the hole in the flange 90. For starting the machine after it has been stopped, the rod 92 is turned by hand until the lug 93engages the bar 94, raising the pin 89 and releasing the feeder. The pin I51 at the same time turns the lever I55, moving the hook i53'to its original position. The machine then stops after the next discharging operation. The time required for the feeder 43 to move after the main switch is opened by the handle 9| is suchthat the last batch of the roasted coffee in the pan II 4 is cooled off and fully discharged through the opening I25, periodically passing over the box I21. The cam 50 extends above the upper edge 43 and is so made that it is resiliently deflected by the lug I53 after turning the arm I55, allowing the movement to continue until the pin 89 engages the hole in the flange 5.

It is understood that my coffee roasting machine may be further modified without depart ing from the spirit of the invention as set forth in the appended claims. i

I claim as my invention:

1. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mounted at one end in the framework, a concave closure partly covering the other end of the cylinder made of a material transparent to radiant heat, means to admit raw coffee into the cylinder, a heat radiating electric lamp in the framework partly entering the concave closure for roasting the coifee in the cylinder by radiation, means to rotate the cylinder, and means to discharge 76 covering the other end of the cylinder, means to admit raw coffee into the cylinder, a stationary radiant heating means outside the cylinder and including a radiant heating element adjacent the closure for roasting the coffee by radiation through the walls of the cylinder, means to rotate the cylinder, and means to discharge the roasted coffee from the cylinder upon completion of the roasting process, the end portion of the cylinderbeing in the form of a cone directed inward with its apex, the closure being in the form of a cone directed inward with its apex toward the first apex and being adapted to transmit said radiant heat to the inside of the cylinder.

3. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mount admit raw coffee into the feeder, the framework having a hopper under the feeder in communication with the cylinder opening, the feeder having an opening registering with the hopper in acharging position, means to rotate the feeder,

thermostatic means in the cylinder to render the feeder rotating means operative when the temperature in the cylinder reaches a predetermined degree, means to maintain feeder rotation after the cylinder has been cooled off by the raw coffee, means to stop rotation of the feeder until the temperature in the cylinder reaches a predetermined degree when said thermostatic means becomes operative, and means to discharge the roasted coffee from the cylinder.

4. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mounted at one end in the framework, means to rotate the cylinder, a feeder rotatively supported in the framework above the cylinder, a contamer for raw coffee above the feeder, means to rotate the feeder, the feeder in a charging position being adapted to admit coffee from the container into the cylinder, an electric heating element outside the cylinder for roasting coffee in the cylinder by radiant heat through the walls of the cylinder, a thermostatic means in the cylinder for starting said feeder rotating means when temperature'reaches a predetermined degree, means to maintain feeder rotation when munication with the cylinder opening, the feeder having an opening registering with the hopper in a char-sin! position, means to rotate the feeder, thermostatic means to render the feeder rotating means operative when the temperature in the cylinder reaches a predetermined degree,

. mostatic means becomes operative, means to discharge the roasted coffee from the cylinder, a manually controlled means to disconnect the supply of power to the machine, and means to render said manually controlled means inoperative until the discharge of the roasted coffee from the cylinder is complete.

6. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mounted at one end in the framework, an electric motor in the framework, means to rotate the cylinder by the motor, means operated by the motor to charge raw coifee into the cylinder, means to roast the coffee in the cylinder, means to discharge the roasted coffee from the cylinder, electromagnetic means including a circuit to control the coffee charging and discharging means. a lever movably supported in the framework, 8. switch on the lever included in said ,circuit of the electromagnetic means for controlling said electromagnetic means, means to move the lever into a position for opening the switch, means to prevent the switch opening movement of the lever until the coffee is discharged from the cylinder, and manually operable means to render the switch opening means fully inoperative.

7. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mount ed at one end in the framework, means to rotate the cylinder, a cylindrical feeder supported in the framework above the cylinder for rotation on a vertical axis, the framework having a hopper connecting the feeder with an opening in the cylinder, means to admit raw coffee into the feeder, the feeder having an opening registering with the hopper in a charging position of the feeder, means to rotate the feeder by the cylinder rotating means, electromagnetic means to connect and disconnect the feeder with the cylinder rotating means, a thermostatic switch in the cylinder for energizing the electromagnetic means to connect the feeder with the cylinder rotating means when the cylinder temperature reaches a predetermined degree, thereby admitting raw coffee into the cylinder, means to deenergize the electromagnetic means to stop rotation of the feeder until cofiee in the cylinder reachessaid predetermined temperature, the cyl-, inder having an opening for admitting raw coffee andfor discharging the roasted product, means to open andto close the opening, and a plurality of cams on the feeder for controlling the cylinder opening and closing means.

8. A coffee roasting machine comprising a framework, a hollow cylinder rotatively mounted at one end in the framework, means to rotate the cylinder, a cylindrical feeder supported in the framework above the cylinder for rotation on a vertical axis, the framework having a hopper connecting the feeder withan opening in the cylinder, means to admit raw coffee into the feeder, the feeder having an opening registering with the hopper in a charging position of the *feeder, ratchet teeth on the periphery of the feeder, a pawl movably supported at the feeder adapted to engage the teeth, means to reciprocate the pawl for rotating the feederyan electromagnetic means for controlling the pawl re ciprocating means, the feeder being adapted to deliver raw coffee into the cylinderymeans for rendering the electromagnetic means operative cylinder reaches, a prewhen temperature the determined degree, means to deenergize the electromagnetic means, thereby stopping the feeder, until temperature of the raw coffee reaches said, predetermined degree, means for discharging the coffee from the cylinder upon completion of the roasting operation, and means controlled by the feeder for operating said discharging means. SANFORD E. RICHESON. 

